This invention relates to a high-resolution 2-dimensional radiation image detector in the form of a plate of a large area, and more particularly to a 2-dimensional radiation image detector which can be applied not only to an apparatus for diagnosis by a radiation image but also to an apparatus for non-destructive inspection or the like which uses a radiation.
An "X-ray/electric conversion apparatus" disclosed in Japanese Patent Laid-Open Application No. Showa 61-62283 and a "Radiation diagnosis apparatus" disclosed in Japanese Patent Publication Application No. Heisei 6-16775 are known as prior art plate-formed radiation image detectors. Those apparatus have a structure wherein optical detectors formed from amorphous silicon or poly-silicon are arranged two-dimensionally on a plate and a phosphor having an equal area to that of the plate is held in close contact with the plate. The phosphor absorbs and converts a radiation into fluorescence, and the optical detectors arranged two-dimensionally detect the fluorescence and convert an image of the radiation into an electric signal. Meanwhile, an apparatus in the form of a plate for imaging a radiation digital image is disclosed in U.S. Pat. No. 5,262,649 entitled "Thin-film Flat Panel, Pixelated Detector Array for Real-time Digital Imaging and Dosimetry of Ionizing Radiation". A further plate-formed radiation image detector is disclosed in U.S. Pat. No. 5,187,369 entitled "High Sensitivity, High Resolution, Solid State X-ray Imaging Device with Barrier Layer".